Help with Raiden PCB problem?

[JackieHarris]

I asked about this over on Arcadeotaku with no luck. Maybe someone here has experience with this PCB and can make a suggestion?

I recently bought a Raiden PCB (original Seibu / Fabtek). I believe it was working when posted but, on arrival, I can't get any picture from it.

I know it needs -5v for sound, and that's fine - I've got it connected up, and the sound works perfectly. It's definitely running, because I can hear credit being inserted, music, game over, etc. plus controls are responsive (I can hear shooting, bombs) but there's just no picture! The screen is completely black, without exception.

I'm running it on a MAK Strike plugged into CRT via RGB scart. Running at 5v (display shows 5v) so shouldn't be a voltage issue. When turned on, the TV does automatically skip to RGB AV, so it's sensing some kind of input (and sound comes through) but there are no signs of video input at all, not even a flash, no scrambled gfx, nothing - just black.

I've also tested it on a friend's supergun (different brand) and it behaves the exact same way. So either both our superguns have a problem, or there's something wrong with the board.

I can see no obvious issues - board is in good condition, all chips are secure, no broken legs, no visible damage or repairs. But maybe if someone knows where I should be looking, perhaps that would reveal something? You can see a photo here: http://imgur.com/DrKwugu

Any suggestions would be very appreciated! Thanks for your time

[antron]

I believe the Raiden boards have funky video refresh rates, your TV may not like it. If you have access to any JAMMA cabinet you should try it there.

[Fudoh]

Indeed. If you're using a TV or broadcast monitor, there's a good chance that it simply can't handle the 54Hz refresh rate.

[alamone]

Raiden 1 is bog standard 60 hz. It should display on almost any monitor.
It is Raiden 2 / DX / Fighters that has a weird refresh rate.

[antron]

Thanks for the correction Al.

[JackieHarris]

Okay, thanks for the info. If the refresh rate is normal then, any other suggestions as to what the problem could be?

[beatsgo]

Okay, thanks for the info. If the refresh rate is normal then, any other suggestions as to what the problem could be?

Do you have an oscilloscope or one you can borrow from someone? Probably want to check the video output including the sync. If not, a multimeter with signal checker can work but only tells you if there's a signal going through the video lines. Oscilloscopes will allow you to check if the generated signals are being transmitted correctly (proper TTL signals, minimal amount of reflection, refractions, and deflections).

[PC Engine Fan X!]

Yep, even the Seibu Kaihatsu SP1 carts of Viper Phase 1 (and it's latter released counterparts: VP1-New Version & VP1-U.S.A.) all have the usual 54hz framerate issue to contend with.

I had this old-school CRT-based Tenika brand name 19" TV monitor with the sole means of video input was a single RF input. By hooking up a Supergun via S-Video into a Composite Video adapter and fed into a Composite Video to RF convertor box, the VP1-U.S.A.'s 54hz framerate came in crystal clear. You could even tate it on it's side and play 'em tate arcade shmup as they were meant to be.

PC Engine Fan X! ^_~

[JackieHarris]

Thanks for the answers, and sorry for the delayed response.

Unfortunately I don't own an oscilloscope (or know anyone who has one) and they look pretty expensive. So I guess I'll have to give that experiment a miss.

Going by responses I've had here and elsewhere, I'm going to conclude this is some strange incompatibility between the board and supergun / TV. I'll just file the PCB away until I have a chance to run it on a JAMMA cab someday